Locking mechanism.



W; D. LUTZ.

LOCKING MECHANISM.

APPLICATION FILE D Nov.26.1913.

Patented Dec. 17', 1918.

E ww UNITED STATES PATENT OFFICE.

WILLIAIVI I). LUTZ, OF ALLENDALE, NEW JERSEY, ASSIGNOR TO OTIS ELEVATORCOM- PANY, OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY.

LOCKING MECHANISM.

Specification of Letters Patent.

Patented Dec. 17, 1918.

Application filed November 26, 1913. Serial No. 803,086.

1 b all whom it may concern Be it known that 1, WILLIAM D. LUTZ, acitizen of the United States, residing in Allendale, in the county ofBergen and State of New Jersey, have invented a.- new and usefulImprovement in Looking Mechanism, of which the following is aspecification.

My invention relates to an improvement in locking mechanism andvembodies a longitudinally movable cylinder in which a key is inserted,which cylinder is actuated by the insertion of the key therein and theinward thrust of the key, and is returned to normal position by anoutward pull on' the key, and the locking mechanism is designed toprevent its use except by one having the proper key. There are many usesfor a locking mechanism of this type, for instance the ignition switchesfor spark coilsin automobile engines require such protection, and alsothe push buttons of a push button controlled electric elevator designedfor private use only, wherein electric circuit closers, commonly calledpush buttons, are located at each floor landing.

Referring to the drawings, Figure 1 shows in section, an elevationalview of a key actuated push button switch constructed inaccordance withmy invention, the various parts therein being shown in their normallocked position; Fig. 2 is a view similar to Fig. l with the push buttonin section but showing the various parts in unlocked position with keyinserted; Fig. 3 is a plan view of Fi 1; F ig. 4 shows in detail anenlarged elevational view of a push button containinga set of tumblerswhich co-act with another set oftumblers to release or unlockthe pushbutton upon the insertion of the proper key therein; Fig. 5 is a planview of Fig. 4, and shows in addition thereto a. view of the key; Fig.dis a sectional elevation view of a modification; Fig. 7 shows indemechanism, in which a key is the controlling factor. The lockingmechanism X comprises a housing 10, provided with a flange 11, whichsupports the housing in the casing, and also serves as a cover therefor.The housing is securely held in position by screws 12, which engagebosses 13 formed integrally with the housing. The latter has an opening26'to receive a metallic push button or look cylinder-B, having asegmental cross sectional area, which coincides with the opening 26 inthe housing and thereby prevents rotation of the push button. The pushbutton is insulated from the contact 4: by an insulating disk 14: havinga button head 14 formed thereon which cooperates with said contact, thedisk being secured to the push button by screws 12'. The button isprovided with an opening 15 adapted to receive the key 9, and with aseries of bores 11, Z), c, and d, which contain tumblers a, b, 0' and d,respectively. The housing 10 is provided with bores e, f, g, and h,matching the bores a, b, c, and d, respectively. Plungers e, f, g and hare inserted in said bores respectively, and are pressed inwardly byspiral springs 16 across the meeting line between- ,the button andhousing, and into holes matching therewith in the button, therebylockingthe button, with the switch mechanism open, as shown. The springsare held in the bores by a cover 17, which engages a slot 18, said coverhaving a prick punch 19 which engages the edge of the bores, and holdsthe cover in place.

The plungers are all the same length, but the tumblers vary in lengthaccording to the desired construction of the key, to guard againstoperation of the switch by one not possessing a proper key.

The tumbler b is larger in cross sectional area than the remaining likemembers, as is the bore f in the housing which is of acorrespondingarea. The key isprovidcd with a high portion 36, which co-acts with thetumbler b when the key is pulled and causes the button to be movedtherewith, and prevents the releasing of the key from the button untilthe latter is in normal position, as hereinafter fully described.

In order to electrically close the switch mechanism C, the key isinserted to its full length into the button, and co-acts with thetumblers to release all the plungers from looking engagement with thebutton, whereupon the inserted key and button are pushed inwardly andmove the free end of the contact 1 into engagement with the contact 2,the inward movement of the limited by a flange 26 formedthereon.

It is found that the friction: incident to the insertion of the keyinto' the button,

causes the button to move inwardly, thereby exerting a slight wedgingaction on the plungers enough to prevent the latter from dropping totheir releasing positions.

To overcome this objectionable feature, I provide two steel balls 21which are contained in bores 22, in the housing. The balls set intodepressions 23, provided therefor on the outer'periphery'of the button,and are positioned to equalize each other, atadiametrically oppositesides of the button. The balls are forced-into the depression bycompression springs 24, which are adjust-' able by means of a screw25.readily be seen that sufficient afforded by the spring pressed balls toresist any inward movement of the button due It will now to the abovenoted cause, but after the key is. inserted to its full length, and afurtherpressure exerted on the key tomove the button inwardly to'close'the contact mechanism, the initial movement ofthe' button causesthe balls to ride out of the depression, thereafter permitting a freeinward movement of the button. 1

The switch mechanism can be maintained closed as long as the key remainsinserted and in order to maintain the button-1n said position, againstthe spring tension of the contact 4, and without requiring a continuedpressure on the key, additional depressions 27 are formed on theperiphery of the but-- ton'l l, into whi'h the balls 21- set, and

thereby offer sufficient resistance to move" ments of the barrel due tothe action of .the'

spring contact 4. due to continued jarring were the lock me'hanismapplied, for-instance. to; an automobile. 1

In restoring the contact mechanism to open position, the key is pulledand the high ,nortion'36 co-actswith the larger tumbler therebyeffecting-a movement of the button therewith. The withdrawal of the keyis not pern1is" ble until the tumbler b is in alinemcnt with'the bore f,whereupon the key-is pulled and the high portion 36 moves the tumblerZginto the bore thereby button being.

resistance is releasing the plungers which fall into locking position,with the contact mechanism open. It is to be noted that thebutton has tobe pulled to its normal position permitting the contact 4 to maintainits normal full open position, before the key can be released. Uponpulling the key, the initial movement of the button causes the balls 21to ride out of the depressions 27, whereupon a free movement of thebutton is had, and the balls willagain set into the depressions 23, whenthe button is again in its normal position. I

In general, the construction of the modification shown in Figs. 6 and 7,is similar to the mechanism herein just described, and

covers the same general principles, the main difference in constructionbeing as follows: Instead of the button and opening .in the housingbeing segmental in cross sectional area to prevent a rotary motion ofthe button after the key is inserted and the button unlocked, I providea slot 28 in the housing whirh is engaged by the top of the key, therebypreventing a rotary motion of the bottom.

Instead of providing four tumblers and. plungers as in the formerconstruction, I provide only two plungers and two tumblers one of thetumblers and its co-act-ing plunger being larger in. cross sectionalarea than the-other like members, for the purpose heretofore set forth,this construction of course, requiring a properly constructed key asshown.

Only one ball 21 is used, which of course requires a depression 29 inthe button, to seat the ball with the button in normal locked position.=

T he construction of: the casing 1 and swit h mechanism C is of a typemore particularly adaptedfor use as a hall push button switch used inconnection ,with an automatic push button electric elevator sys-' tem.wherein the casing is let into a wall or partition, the-said anddescribed in my co-pending application, SerialNo. 754,463, filed :March15, 1913.

'In the additional and after the key is inserted to its full length'intothe button, the button. is rotated a certain amount before it can bepushed inwardlv to close the contact mechanism.

1 In th s construction the button is provided with abutments 31 and 32having heads 33 thereon, screw threaded to engage corre-.

the l ev' is-inserted to its full length in othe button, unlocking thesame. and the key is" then-turned to rotate the button until the partsbeing fully shown.

. modification conipris. ing lgs. 8.?9; and 10, the plungersanjdtumblers" are all similar in cross section .area

abutments are in alinement with grooves '35 in the housing. The buttonis now pushed inwardly by the keys, thereby closing the contactmechanism. In. restoring the contact mechanism to open position the keyis pulled carrying the button with it, and when the abutments ride outof the grooves, the key is turned to rotate the button to its normalposition with vthe bores and tumblers in proper alinement, thereupon thekey can be released thereby permitting the plungers to fall into lockingengagement with 'the'button. In an application of my invention to anautomobile, the contacts 2 and a, constitute the magneto connection, and'I provide an additional contact 2 (see Fig. 1) for the batteryconnection. The contact 2 is positioned to be engaged by the contact 4,upon the initial movement thereof, and if desired the circuittherebetween can be maintained, without continued pressure on the key,by providing additional depressions in the button into which the balls21 set.

when the button is pushed-inwardly enough to close the said contacts.'The push-button device herein just described may readily be adapted foruse as acircuit opener instead of a circuit closer by slightrearrangement of the contact mechanism, and it is obvious that variousother modifications in the details of construction and arrangementofparts can be made by those skilled in the art without departing from thespirit and scope of my invention, therefore I do not wish to be limitedto the precise construction and ar rangement of parts herein shown.

What I claim is 1. The combination with a locked push button having adepression therein, and adapted to receive a key to unlock the buttonfor operation, and means adapted to engage the depression and preventmovement thereof caused by friction incident to the introduction of thekey into the button.

2. In a device of the class described, a

I locked push button having a depression therein, and adapted to receivea key to unlock the button for operation, and adjustable yielding meansadapted to engage the depressions and maintain the button in'itsoperated position.

3. In a device of the class described, a locked push button having adepression therein and adapted to receive a key to un lock the buttonfor operation, and yielding means adapted to engage the depression.

4. The combination with a push button, of a key removably engaged in thebutton, means engaging the button and adapted to be liberated by theinsertion of the key and release the button for operation, and frictionmeans, to prevent a movement thereof caused by the friction incident tothe introduction of the key into the button.

5. The combination with a push button, of

button;andadapted to be liberated bythe' insertio'irof'the key an-drelea se the button for operationfand yielding means 'frictionallyengaging the" button toprevent a wedging action thereof against thetransverse mem bers, upon theinsertion ofthe key nto the button p 7; Inadevice-0r the classf described, a p'uslfbutton, a key removably engagedin the b-utton, transverse members engaging the button and adaptedtobeliberated bythe insertion of the'key and release "the button foroperation, a yielding friction member and depressions in the button toseat the yielding member when the button is in locked position, and in.operated position.

8. In a device of the class described, a push button, a key removablyengaged in the button, means engaging the button and adapted to beliberated by the insertion of the key and release the button foroperation, a yielding friction member, depressions in the button adaptedto seat the yielding member when the button is in locked position, andin operated position, and an additional depression to seat the yieldingmember at an intermediate point of operation of the button.

9. In a device of the class described, a normally locked push button, akey removably engaged in the button, a friction member, a depression inthe button adapted to seat the friction member with the button in itsnormal locked position, another depression in the button adapted to seatthe friction member with the push button in operated position, and meansengaging the button adapted to be liberated by the insertion of the keyand release the button for operation, said means comprising a pluralityof plungers and co- 7 acting tumblers, one of the plungers and itsmatching tumbler being larger in cross sectional area than the remaininglike members to permit the releasing of the key from the button onlywhen the button is in normal position to be locked.

10. In a device of the class described, a casing, a push button, ahousing for the push button fixed to the casing and having a flangethereon to cover the casing, the push button being segmental in crosssectional area, and co acting With a corresponding area in the housingto prevent rotation of the push button, a key removably engaged in thebutton, spring pressed plungers contained in the housing and engagingthe button, tumblers contained in the button, the tumblers matching theplungers and co-acting therewith to release the button for operationupon the insertion of the key into the button, one of the plungers andits matching tumbler being larger in cross section than the remaininglike members, to permit removal of the key from the button only when thebuttonis in normal position to be locked, a friction member, adepression in the button to seat the friction member with the button inits normal locked position, and another depression adapted to seat thefriction member with the button in its operated position.

11. In a device of the class described, a locked push button, a. keywhich unlocks and actuates the button by one and the same or continuedthrust thereof into the button,

and means which are selieacting, for maintaining the button in anactuated position, and for releasing the button by a pull on the latter.

12. In a device of the class described, a locked push-button adapted toreceive a key which unlocks and actuates the button by one and the sameor continued thrust into the button, and self-acting means formaintaining the button in its full operated position and in anintermediate point of operation, said means releasing the button fromeither position by movement of the button.

In testimony whereof, I have signed my name to this specification in thepresence of two subscribing witnesses.

WILLIAM D. LUTZ.

Witnesses VVALTER G. STRANG, AMES G. BETHELL.

Copies of this patent may be obtained for fivecents each, by addressingthe Commissioner of Patents,

Washington, I). 0."

